/*
 * Copyright � 2002-2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System.Reflection;

namespace Spring.Aop.Support;

/// <summary>
/// Various <see cref="Spring.Aop.IPointcut"/> related utility methods.
/// </summary>
/// <remarks>
/// <p>
/// These methods are particularly useful for composing pointcuts
/// using the union and intersection methods.
/// </p>
/// </remarks>
/// <author>Rod Johnson</author>
/// <author>Aleksandar Seovic (.NET)</author>
public sealed class Pointcuts
{
    /// <summary>
    /// Creates a union of the two supplied pointcuts.
    /// </summary>
    /// <param name="firstPointcut">The first pointcut.</param>
    /// <param name="secondPointcut">The second pointcut.</param>
    /// <returns>
    /// The union of the two supplied pointcuts.
    /// </returns>
    /// <seealso cref="Spring.Aop.Support.UnionPointcut"/>
    public static IPointcut Union(IPointcut firstPointcut, IPointcut secondPointcut)
    {
        return new UnionPointcut(firstPointcut, secondPointcut);
    }

    /// <summary>
    /// Creates an <see cref="Spring.Aop.IPointcut"/> that is the
    /// intersection of the two supplied pointcuts.
    /// </summary>
    /// <param name="firstPointcut">The first pointcut.</param>
    /// <param name="secondPointcut">The second pointcut.</param>
    /// <returns>
    /// An <see cref="Spring.Aop.IPointcut"/> that is the
    /// intersection of the two supplied pointcuts.
    /// </returns>
    public static IPointcut Intersection(IPointcut firstPointcut, IPointcut secondPointcut)
    {
        return new ComposablePointcut(
                firstPointcut.TypeFilter, firstPointcut.MethodMatcher)
            .Intersection(secondPointcut);
    }

    /// <summary>
    /// Performs the least expensive check for a match.
    /// </summary>
    /// <param name="pointcut">
    /// The <see cref="Spring.Aop.IPointcut"/> to be evaluated.
    /// </param>
    /// <param name="method">The candidate method.</param>
    /// <param name="targetType">
    /// The target <see cref="System.Type"/>.
    /// </param>
    /// <param name="args">The arguments to the method</param>
    /// <returns><see langword="true"/> if there is a runtime match.</returns>
    /// <seealso cref="Spring.Aop.IMethodMatcher.Matches(MethodInfo, Type)"/>
    public static bool Matches(
        IPointcut pointcut, MethodInfo method, Type targetType, object[] args)
    {
        if (pointcut != null)
        {
            if (pointcut == TruePointcut.True)
            {
                return true;
            }

            if (pointcut.TypeFilter.Matches(targetType))
            {
                IMethodMatcher mm = pointcut.MethodMatcher;
                if (mm.Matches(method, targetType))
                {
                    return mm.IsRuntime ? mm.Matches(method, targetType, args) : true;
                }
            }
        }

        return false;
    }

    /// <summary>
    /// Are the supplied <see cref="Spring.Aop.IPointcut"/>s equal?
    /// </summary>
    /// <param name="firstPointcut">The first pointcut.</param>
    /// <param name="secondPointcut">The second pointcut.</param>
    /// <returns>
    /// <see langword="true"/> if the supplied <see cref="Spring.Aop.IPointcut"/>s
    /// are equal.
    /// </returns>
    public static bool AreEqual(IPointcut firstPointcut, IPointcut secondPointcut)
    {
        return firstPointcut.TypeFilter == secondPointcut.TypeFilter
               && firstPointcut.MethodMatcher == secondPointcut.MethodMatcher;
    }

    /// <summary>
    /// Creates a new instance of the
    /// <see cref="Spring.Aop.Support.Pointcuts"/> class.
    /// </summary>
    /// <remarks>
    /// <p>
    /// This is a utility class, and as such has no publicly
    /// visible constructors.
    /// </p>
    /// </remarks>
    private Pointcuts()
    {
    }

    // CLOVER:ON
}
